NLLW – návod k obsluze a instalaci
Here you can see that when is set high volume of microphone (MIC)
as same as speaker (VOL) then signals influence each other. The result might
be that call is interrupted or one direction is silent.
The loudspeaker as same as microphone are connected by wires as
you can see on picture 1. Caution on polarity of microphone because is
powered (+ -)
The jumper marked SERVICE is available for automatic enter to
programming mode when password is forgotten. When jumper is ON And you
make incoming call on LLW then after picking up you are directly in
programming mode. In programming mode you can change all parameters
includes new password as well.
The black connector on opposite side from screw terminal is designed
for PC connection by special cable KAB. The cable is galvanicaly isolated
convertor of RS 232 interface (PC port COM1, COM2…) and LLW interface.
Galvanical isolation is necessary because PC might be grounded And
telephone line MUST NOT be grounded! When your PC is not equipped by RS
232 port but only USB then you can use convertor USB-RS232 for its is in your
PC creates virtual serial port (for example COM6) and this you will select in
configuration software LiftSet for communication to LLW.
1.3.2 Telephone line connection (LINE a b)
The basic condition for LLW operation is telephone line connection.
Telephone line is 2 wires which you connect to screw terminal up picture 2.
Picture 2: Telephone line connection
Telephone line interface has following typical parameters. The voltage in
Hang up status (disconnect loop) 20-60V = (during connection not depends on
polarity), when LLW pick up (active status) on telephone line is cca 7-12V,
depends on line current which is in range 20-60mA. Further telephone line
parameters are signaling, ringing (incoming call) is define by AC voltage from
50-90V and frequency 20 – 60Hz. To the signaling belongs even tones, have
